From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FC23C43610 for ; Mon, 26 Nov 2018 22:16:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A6952082F for ; Mon, 26 Nov 2018 22:16:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A6952082F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727474AbeK0JMZ (ORCPT ); Tue, 27 Nov 2018 04:12:25 -0500 Received: from mga06.intel.com ([134.134.136.31]:12616 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726397AbeK0JMZ (ORCPT ); Tue, 27 Nov 2018 04:12:25 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Nov 2018 14:16:49 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,284,1539673200"; d="scan'208";a="284119291" Received: from jsakkine-mobl1.jf.intel.com (HELO localhost) ([10.24.8.61]) by fmsmga005.fm.intel.com with ESMTP; 26 Nov 2018 14:16:48 -0800 Date: Mon, 26 Nov 2018 14:16:49 -0800 From: Jarkko Sakkinen To: "Dr. Greg" Cc: Andy Lutomirski , Andy Lutomirski , X86 ML , Platform Driver , linux-sgx@vger.kernel.org, Dave Hansen , "Christopherson, Sean J" , nhorman@redhat.com, npmccallum@redhat.com, "Ayoun, Serge" , shay.katz-zamir@intel.com, haitao.huang@linux.intel.com, Andy Shevchenko , Thomas Gleixner , "Svahn, Kai" , mark.shanahan@intel.com, Suresh Siddha , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Darren Hart , Andy Shevchenko , LKML Subject: Re: [PATCH v17 18/23] platform/x86: Intel SGX driver Message-ID: <20181126221649.GE868@linux.intel.com> References: <20181120120442.GA22172@linux.intel.com> <20181122111253.GA31150@wind.enjellic.com> <20181124172114.GB32210@linux.intel.com> <20181125145329.GA5777@linux.intel.com> <0669C300-02CB-4EA6-BF88-5C4B4DDAD4C7@amacapital.net> <20181125185524.GA23224@wind.enjellic.com> <94154ECB-3EF7-4A37-9057-0B84DBCE650E@amacapital.net> <20181126110038.GA27609@wind.enjellic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181126110038.GA27609@wind.enjellic.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 26, 2018 at 05:00:39AM -0600, Dr. Greg wrote: > We will be interested in your comments as to why the proposal is > insufficient in the real world of FLC. > > I believe the proposed architecture can be defended as being effective > in the real world, as it allows the root user to use cryptographic > protections of access to the PROVISION bit and to enclave execution in > general. On FLC that is the strongest guarantee that can be > delivered. > > When we speak of 'unauthorized' users I believe we are speaking in the > parlance of discretionary access controls which has a much wider TCB > scope then the cryptographic model we are proposing. The model we > propose allows the platform owner (root) to effectively implement the > same level of security over the PROVISION bit that current locked > platforms have, in a free and open fashion of course. > > We can certainly attempt to explain our position further. I think kernel controlled provision would in all cases lower the mitigations of thread scenarios (at least what you've presented so far) assuming that a compromissed kernel could be detected fairly quickly, wouldn't it? Even without SGX, having a compromissed kernel, you can anyhow stealth your malware in many ways. /Jarkko